Collapsing tap.



PATENTED OCT. 9,- 1906.

E. M. BUGKIUS. GDLLAPSING TAP,

. w Y gg +520 l l ffl@ No. 832,716. PATENTED OCT. 9, 1906.

' E. M. BUGKIUS.

COLLAPSING TAP.

APPLICATION FILED DB0. 11. 190s.

2 SHEETS-SHEET 2. fj

UNITED sTATEs PATENT oEEIcE.

Specification of Letters Patent.

Patented Oct. 9, 1906.`

Application filed December l1, 1903. Serial No. 184,792.

Y drawn.

A further object of the invention is to provide improved means whereby the collapse of the tap may be effected automatically when the tap has reached t-he desired depth, and in this connection my invention provides for adjustment of the depth at which this action shall take place.

Another important object of my invention is to provide for reamin' or .undercutting the hole in advance of or be ow the tap-dies so as to clear the scale and bring the hole to exact size for operation of the tap-dies without the use of separate tools for that purpose.

An object of the invention is to provide a running -tap with which to cut threads in pipe-elbows and other fittings where the screw-threads are required to extend as close as possible to the end of the way into which the tool must be inserted while cutting the thread. I accomplish this object by providing a tap having a cutter and a chaser, the chaser being located rearwardly of the cutter both axially and circumferentially of the tap and terminating approximately in a plane in which the cutterextends and which cuts the tap at right angles to its axis.

In the practical form I deem preferable the back of the cutter is practically in the plane of the front of the chaser, the terms "bac/k and front being here used with reference to the axial movement of the tap in the act of cutting, and the front of the cutter is brought as close to the front end of the tap as the strength of the material will admit.

Owing to the hard scale in pipe-fittings and other rough castings the life of the dies or chasers ordinarily used for tapping the same will be greatly prolonged by reaming the hole in advance of the chasers. This invention enables such reaming to be accomplished at the same operation with the tapping of a-liole in an elbow or elsewhere practically to the end of the hole.

Another object is to provide a simple construction of means for catching and releasing the collapsincv mechanism. This I do by providing a sliding catch on the outside of the body of the tap, the same being mounted thereon by means of a sleeve and arranged to engage a handle which projects outward from the barrel which has the cams that move the chasers.

Qther features and objects of the invention will appear in and from the followingdescription and claims.

The accompanying drawings illustrate the invention.

Figure I is a plan of the tap with the shank in section. Fig. II is a side elevation thereof with the dies or chasers expanded. Fig. III is a section on the line III III in Fig. IV with the parts in collapsed position, only one of the dies or chasers being shown. Fig. IV is a section on the line IV IV in Fig. I. Fig. V is a detail elevation of the die-operating barrel. Fig. VI is a plan of the bottom plate of the tool. Fig. VII is a section on the line VII VII in Fig. II. Fig. VIII is a section on line VIII VIII in Fig. IV. Fig. IX is an elevation at right angles to Fig. I showing the dies or chasers in retracted position'. Fig. X is a plan of the spring device for effecting collapse of the tap. Fig. XI is a perspective view of one of the dies or chasers. Fig. XII is a fragmental section on the line XII XII in Fig. VI.

l designates the shank or spindle of the tap, and 2 the body or dieholding memberl thereof, which is desirably cylindrical and is fastened or screwed to the shank in the usual manner. Any desired number of radial slots or channels 3, formed in the lower end of Vthis 4 body 2, serve to receive the dies or chasers 4,

which are slidable in said slots and project at their inner ends into a cylindrical chamber or recess 5 in the lower part of the member 2, said chamber containing the various operating parts for the dies or chasers. A plate or disk 6, secured by screws 7 and pins 35 to the bottom of member 2, serves to close the lower end of slots 3 and recess 5 and also serves to carry the reaming, sizing, or clearing cutters 8. Said cutters are seated in radial slots 9 in plate 6, and screws l0, working in the plate and engaging with the inner ends of said cutters, serve to adjust the radial projection of same, clamp-screws 11 serving to hold the cutters firmly in position when adjusted.

The end plate 6 has on its front face a re- IOO IIO

cess 62, from which the holes for screws 10 extend radially outwardly, so that the heads of said screws are accessible through the recess 62 from the end of the tool. By mounting the cutters and their adjusting meansin the plate facility of construction is secured, and by the removal of the plate the cutters and their adjusting means are removed and access is given to the interior of the tool. When the screws 11 aretightened, the backs of the cutters are forced against the front end of the body 2, and thus held in the plane in which the fronts of the chasers terminate, so that as'the tap is advanced and rotated each chaser practically cuts at once in the path cleared by its preceding cutter, and thus it is made possible to tap a hole closer to the bottom than possible with any reaming-tap heretofore known.

'By making the cutters independently adjustable and providing independent adjust-v ing means for each cutter it is made possible to keep the tool true regardless of the uneven wear of the cutters, and itis made possible to withdraw and replace any cutter by simply loosening the binding-screw 11 and without changing the adjustment of any other cutter. With this independent arrangement of cutters a tap adapted for a plurality of cutters may be used with its full complement or any less number of cutters with equal facility. I prefer to use three or more cutters, depending on the diameter of the tool, in orderto equalize the strain.

Another advantage arising from the use of independent cutters is the ease with which any cuttervmay be removed or replaced at any time without disturbing the others or requiring an entirely new tool, as the case of breakage.

The inner face of the plate 6 is provided with projections 6', preferably segmental, between which are formed radial grooves 3. The grooves 3 register with the grooves 3 in the body 2 and receive the lower ends of the dies 4. This causes the dies to bear most of the rotative strain that is placed upon the plate by the cutters 8, and thereby makes a strong construction with comparatively light material. The projections also extend up into the cavity or recess of the body 2 of the tool, as shown in Fig. XII, and thereby centers the plate, so that the cutters 8 travel in a true circle concentric with the circle traveled by the chasers 4. They also increase the amount of stock at the points where the screws` 10 pass through, therebyincreasing the strength where it would otherwise be weakenedby the screw-hole.

The radial grooves 9 are made in the top of plate 6, so that when the plate is secured in position on the lower end of the body 2 by the screws 7 the tops of the cutters are substantially on a line with the lower ends of the chasers 4, so that the chasers follow immedicutters so far in advance of the taps asi nec- Y essary where they are arranged longitudinally of the tool instead of radially.

Another advantage arising from the use of such a plate is the ease with which the adjustment of the cutters can be effected from the bottom of the tool, as all that is necessaryis to adjust each cutter by means of its screw 10 and then tighten it against the lower end of the body 2 by its screw 1 1. In case of breakage the broken cutter can be taken out by loosening its screw 11, which will also permit of the insertion of the new cutter, which can then be adjusted by its screw 10 and fastened by the screw 11, and if it be desired to use the tool as a cutter only all that is necessary is to retract the chasers and leave the cutters projecting the required distance, or the cutters may be removed or a plane plate substituted for the plate 6 and the tool used as a tap by projecting the chasers 4.

12 designates an operating barrel or cylinder rotatable on a shaft or centering means 13. rl`his barrel comprises a die-expanding cam hub or collar 14, a die-collapsing camplate 15, and anoperating-collar 16, all fastened together and to shaft 18, so as to move as a single unit, the collar 16 fitting and turning within the sleeve-recess 5 ofthe tap-body. Collar 16 is provided with ahole or seat for an operating-handle 17, whereby the barrel may be turned. Cam-faces 18 on the collar 14 engage with the inner edges of dies 4 when the barrel is turned by handle 17 in the direction opposite-to the arrow in Fig. Hl to force the dies outwardly, these edges being beveled to give a better bearing for this purpos'e. Cam device 15 has cam-slots `19 engaging pins 2O on lugs 21, extending upwardly from the respective dies 4, so that when the barrel 12 is turned in the direction of the arrow in Figs. IH and VIII the dies will be drawn inwardly or collapsed. Such movement of the barrel is effected by a spring 22, connected at one end to collar 16 and at the other end to the body 2 of the tap.

A shouldered collar or sleeve 23 surrounds the body 2 of the tap and may be adjusted circumferentially or angularly around the same, being clamped in desired position by clamp-screws 24, working in slots 25 in said collar. Handle 17 passes through a slot or notch 26 on the sleeve 23. When moved in one direction, the handle 17 engages with a locking device consisting of a slide 27,l movable vertically in'a guide or way 28, formed by the shoulders of the sleeve, and having a catch or seat 29, adapted to engage over and catch the handle, this slide falling into catching position by gravity. A tappet-block or IOO controlling device 30 is connected to and slidable vertically on the slide 27, being adjustable thereon by a screw 81, so as to vary the longitudinal position oi a roller 32 on the lower end oi said block, which is adapted to engage the work or part being operated upon to` raise the slide relatively to the tap-body and withdraw the catchthereon from the handle 17, and the barrel 12 springs back under the influence of spring 22, thereby collapsing the dies through the action oi camslots 19. 4Screw 38 on block 30, working between stops 39 39, ixed on sleeve 23, limits the movement of the locking device and prevents the slide 27 rom coming out oi' the way 28.

The cam-faces 18 give an even bearing substantially from top to bottom of the tapdies, as distinguished from the liability to uneven or partial support given by wedges or plugs.

By adjusting the circumferential position of collar 23 the eiiective stroke of handle 17 is limited so as to stop the cam at the proper point to give the desired expansion of the ies.

An annular oil-channel 36 is provided in the top of the body portion 2 of the tool,and ducts A37 lead therefrom downwardly and then outwardly to discharge oil directly over the dies. Dies 4 are removable, slots 33 being made in the cam-hub 14 to enable insertion of lugs 21 and pins 20 into engagement with cam device 15.

To permit of the rotary movement of the barrel without interfering with the lugs 21, the barrel is recessed circumferentially or provided with a space between the cam device 15 and the hub 14, within which the lugs are seated as soon as the barrel is rotated. The lugs 21 are inserted into the recesses 38 and the pins 2O into the slots 19 as the blades or chasers 41 are inserted into the deepest portions of the longitudinal recesses forming the cam-faces 18, after which the chasers are moved up so that the lugs are in the plane of the circumferential recess, where they are held by the plate 6 at the lower end of the body. The depth of the recesses 33 is just suflicient to permit of the insertion of the lugs without having the pins engage with the lower surface of the cam-plate 15.

In operation the sleeve 23 is adjusted to the proper position for the desired cut of the tap-dies, and the controlling device 30 is adjusted according to the distance it is desired to tap into the hole. The undercutters or reamers 8 are also adjusted to cut the hole to the proper size for the action of the tappingdies. Handle 17 being turned until it engages with the catch 29, the cam-faces on collar 14 force out the dies to the proper extent. Then the tool is entered in the hole, and on being rotated its collars 8 iirst clean the hole of scale and bring it to proper size, and the tapping-dies then cut the threads. When the hole has been tapped to the proper depth,

the controlling device 30, as above described, releases the locking-catch 29 and allows the working barrel to be moved back automatically by action of spring 22, the cam-plate 15 causing the dies to be drawn in or collapsed, enabling the withdrawal of the tool.

The construction above described may be variously` modied without departing from the spirit of my invention. For example, the various parts of the working barrel may be rigidly connected in any suitable manner, as by being formed in one integral piece.

What I claim, and desire to secure by Letters Patent of the United States, is-

1. In a collapsing tap, a recessed and longitudinally-slotted body, a circumierentiallyrecessed barrel rotatably mounted in the body, the portion of the barrel on one side of said recess being provided with cam-slots,

Aand the portion on the other side being provided with recessed cam-iaces, chasers mounted in the slots of the body and engaged by said cam-faces, an extension carried by each of said chasers for fitting in one of said camslots, and a plate at the end of the body.

2. The combination of a tap-body, dies carried thereby, a barrel rotatable within the tap-body and having cam portions engaging said dies, operating means connected to the barrel, a member movable around the tapbody and angularly adjustable thereon, a slide mounted on the said member and having a catch portion to engage the operating means aforesaid, a trip evice movably mounted on said slide, a screw on the slide engaging the trip device for adjustment thereof longitudinally of the tap-body, and a spring for rotating the barrel.

3. A collapsing tap comprising a body provided with radially-movable chasers, means for moving the chasers, a grooved plate at the end of body, cutters in said grooves, and means carried by the plate for adjusting the cutters.

4. In a collapsing tap, a body provided with radially-movable chasers, means for moving the chasers, a plate at the end oi the body provided with radial grooves in the surface adjacent to said body, and with projections extending into the body and engaging the chasers, a cutter in each groove, means for adjusting the cutters longitudinally, and means for clamping them against the end of the body.

5. In a collapsing tap, a body provided with radially-movable chasers, means for moving the chasers, a plate on one end oi the body, one surface of which is recessed and the opposite surface is grooved radially and is engaged with the chasers, the portions of the plate at the bottom and at the inner end of each groove being each provided with a screwthreaded hole opening into the recess, a cut- IOO ter in each groove, and a screw in each of said `openings for engaging With and adjusting the the body provided with projections for fitting in the recess of the body for centerin@ the plate, and radially-arranged cutters adjustlably mounted in the plate.

7. In a collapsing tap, a recessed and longitudinally-slotted body, a plate at one end of the body, one face of Which is provided with segmental projections for iitting in said recess and centering the plate, said projections being spaced apart to form grooves to register with the slots in the body, radiallymovable chasers in said slots, one end of each of which lits in its respective groove in the plate, and means for moving the chasers.

8. In a collapsing tap', a recessed and longitudinally-slotted body, a circumferentiallyrecessed barrel rotatably mounted in the body, the portion of the barrel on one side of said recess being provided With cam-slots and the portion on the other side being provided With recessed cam-faces, chasersmounted in the slots of the body and engaged by said cami'aces, one end of each of Which chasers is provided With a lug, a pin on each lug for fitting in one of said cam-slots, and a plate at the end of the body.

9. In a collapsing tap, a body, radiallymovable chasers mounted'therein, a rotatable member for moving the chasers, a handle projecting from said member, a shouldered sleeve rotatably mounted on the body, means for adjustably locking the sleeve against rotasaid Way provided With a notched portion for engaging with the handle, and means for automatically releasing the slide from the handle.

l1. In a collapsing tap, a body, radiallymovable chasers mounted therein, a rotatable member for moving the chasers, a

i spring-actuated handle projectin from said member, a recessed sleeve rotatab y mounted on the body, means for adjustably locking the sleeve against rotation, a longituidnallymovable notched slide for engaging with the handle, a tappet on the slide, means for limiting the movement of the tappet, and means Jfor moving the slide to release the handle at any desired predetermined point.

In testimony whereof I have signed my name to this speciiication, in the presence of two subscribing Witnesses, at Los Angeles, in the county of Los An eles and State of California, this 4th day offlecember, 1903.

EDWARD M. BUCKIUS.

Witnesses:

ARTHUR P. KNIGHT, JULIA ToWNsEND. 

